The present invention generally relates to a lighting or illumination assembly. More particularly, the present invention relates to a lighting or illumination assembly that uses an array of light emitting diodes (LEDs).
Illumination systems are used in a variety of diverse applications. Traditional illumination systems have used lighting sources such as incandescent or fluorescent lights, for example. More recently, other types of light emitting elements, and light emitting diodes (LEDs) in particular, have been used in illumination systems. LEDs have the advantages of small size, long life and low power consumption. These advantages of LEDs make them useful in many diverse applications, and LEDs are frequently replacing other lighting sources.
For many lighting applications, it is necessary or desirable to have a plurality of LEDs supply the required light intensity and/or distribution. For example, a plurality of LEDs can be assembled in an array having small dimensions to provide a high illuminance in a small area, or a plurality of LEDs can be distributed over a larger area to provide a broader and more uniform illuminance.
LEDs in an array are commonly connected to each other and to other electrical systems by mounting on a printed circuit board. However, when LEDs are required to be distributed over a large area (as when backlighting a large high performance display device, for example), the use of a printed circuit board becomes problematic for several reasons. For example, printed circuit boards may be difficult to produce and/or handle in the sizes and shapes required for some display devices (e.g., very long and narrow strips). The rigidity of the printed circuit board material may make manufacturing or assembly difficult, especially where the printed circuit board must conform to a non-planar shape. Additionally, the heat dissipation requirements of the LEDs may not be met by conventional printed circuit board constructions. Therefore, an illumination assembly that addresses these problems is needed.